Field of Technology
The present disclosure relates to an organic light-emitting diode (OLED) display panel, and more specifically to an OLED display panel with an improved color gamut ratio.
Description of the Related Art
An organic light-emitting diode (OLED) is a device capable of producing light on its own. Accordingly, a lighter and thinner display device that does not require an additional light source, unlike a liquid crystal devices LCD, can be manufactured using OLEDs. Further, OLEDs have advantages in that they are driven with low voltage to thereby consume less power. Further, they reproduce better colors and have good response speed, wider viewing angle and good contrast ratio (CR). For these reasons, an OLED display panel using such OLEDs is currently under development as the next generation display device.
In order to produce light of full-color, an OLED display panel includes red, green and blue pixels. A red light-emitting layer, a green light-emitting layer and a blue light-emitting layer may be patterned in a red pixel, a green pixel and a blue pixel, respectively, using a fine metal mask (FMM).
As the latest display devices are equipped with high resolution, the demand for a larger screen is ever increasing. As display screens become larger, pixel patterning using a FMM may not be applicable due to misalignment. Misalignment occurs when a center portion of a FMM is drooped due to its weight and ultimately fails to form a light-emitting layer at a desired location.
In order to overcome the problem, a proposed method of stacking several common organic light-emitting layers on the entire surface of an OLED display panel has been proposed. More specifically, light generated in several organic light-emitting layers that are stacked on the entire surface of the device are mixed to produce white light. The white light passes through the color filter layer in each of pixels to be represented as red light, green light and blue light. Forming several common organic light-emitting layers in this manner does not require the use of a FMM. Accordingly, the possibility of misalignment caused by a FMM is eliminated.